<?php

abstract class Update_Model_Database_AbstractChange
{
    /**
     * @var Zend_Db_Adapter_Abstract
     */
    protected $db;

    protected $comment=false;

    /**
     * Build and initialize the object
     *
     * @param Zend_Db_Adapter_Abstract $db          Database adabpter to use
     * @param string                   $tablePrefix Prefix for any table names
     */
    public function __construct(Zend_Db_Adapter_Abstract $db)
    {
        $this->db = $db;

    }

    /**
     * Getting comment from previus operation;
     */
    public function getComment(){
			return $this->comment;

    }

    /**
     * Set comment form current database change
     */
    protected function setComment(){


    }

    /**
     * Changes to be applied in this change
     *
     * @return null
     */
    abstract function up();

    /**
     * Rollback changes made in up()
     *
     * @return null
     */
    abstract function down();

}